The South Beach Diet , which became a bestseller eight years ago, is intended for weight loss.

The doctor who created it noticed some of his patients were experiencing unexpected health benefits. Dr. Arthur Agatston has since realized he has since realized cutting out gluten is the main reason why.

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Agatston points to Novak Djokovic as a famous example of someone who has benefitted from removing gluten from his diet.

“The famous tennis player Djokavic turned around his career. He was always great but he would fade in the fourth and fight set until he went off gluten,” said Agatston.

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This year he won Wimbledon and the US Open.

In his newest book "The South Beach Wake Up Call" Agatston suggests many of us have some degree of gluten intolerance and don't know it.

“The South Beach Gluten Solution is to eliminate all wheat products, rye, barley that means you can't drink beer for about a month,” he said.

It didn't take long for his nurse practitioner Clarissa Gregory to notice a dramatic difference in her acid reflux.

“Dr. Agatston said just try to for two weeks and I'm somewhat of a skeptic but I felt so badly I said let me try it and literally within two days, it was unbelievable,” she said.

Lean protein, nuts, beans and plenty of vegetables, that's phase one of The South Beach Diet. No wheat products for the first two weeks. That caused more than weight loss for some dieters.

“One of our patients who went on phase one primarily for weight loss had horrible psoriasis and was about to go on a very toxic medication to clear it , and on the first phase of the diet which is wheat free her psoriasis completely disappeared.” said Agatston.

There are a growing number of gluten-free bread, pastas and other products on the market. To avoid gaining weight, Agatston recommends avoiding items made with white rice and sugar.

He also points out that gluten intolerance affects children as well. He advises if your child has stomach issues, skin problems or allergies, talk with the pediatrician about a gluten free trial to see if symptoms improve.